Perceived Social Support as a Mediator in the Link between Loneliness and Well-being: Insights from the Transactional Model and Stress-Buffering Hypothesis

International university students frequently encounter psychosocial challenges, including loneliness, cultural displacement, and limited social integration, which can undermine psychological well-being. Yet the role of perceived social support as a psychological mechanism linking loneliness to well-being in non-Western academic contexts remains under-examined. This study investigated whether perceived social support mediates the association between loneliness and psychological well-being among international students in Türkiye. Using a cross-sectional design, data were collected from 1,136 undergraduate international students who completed validated self-report measures of loneliness, perceived social support, and psychological well-being. Structural equation modeling with bootstrapped mediation analysis was employed to test the hypothesized relationships. Results indicated that loneliness was negatively associated with both perceived social support and psychological well-being, whereas perceived social support was positively associated with well-being. Mediation analysis revealed a significant indirect effect of loneliness on psychological well-being through perceived social support, with the direct association substantially reduced when support was included in the model. These findings highlight perceived social support as a central psychological mechanism through which loneliness affects well-being, underscoring the importance of culturally responsive interventions aimed at strengthening students’ perceptions of social support. Findings are interpreted within the transactional stress model and the stress-buffering hypothesis.